This application extends an outcome study of acute treatment (NIMH Grant #57727; "Effectiveness of Community Services for Conduct Problems") that compares Community-based (n=72) and Clinical-based (n=72) multimodal treatment protocols for young children (ages 6-11) with a diagnosis of Oppositional Defiant Disorder or Conduct Disorder. The two specialty treatments are being compared to treatment-as-usual in the same health system (TAU; n=40) through a recent supplement (MH 57727-02S1; 6/1/00) and to a fourth comparison group composed of matched healthy controls (CONT; n=60; NINR Grant #07615; 10/1/00). Outcome assessments were conducted at pre- and post-treatment, and at 6-, 12- and 24-month follow-ups. Preliminary outcome (pre-post) analyses indicate higher rates of treatment completion and some differential rates of recovery from ODD or CD favoring the Community (vs. Clinic) condition, and many overall improvements, but few group differences, on clinical outcomes. In addition, specialty treatment shows several improvements on these measures, relative to TAU. This renewal application extends this work by incorporating a novel, long-term assessment and follow-up care phase to address these aims: 1) document the long-term (36-month) follow-up effects of acute treatment, 2) evaluate a booster treatment protocol that is designed to enhance long-term outcome by promoting the maintenance of existing gains and preventing other adverse, high-risk outcomes, and 3) examine multivariate models (individual, contextual, treatment variables) to predict long-term outcomes in this large patient sample, now aged 9-16 years. The specialty treatment cases will be considered for randomization to the booster protocol or routine follow-up care conditions. All four samples will participate in assessments conducted at 36-mos. follow-up (pre-booster assessment), six months later (post-booster treatment; at 42-mos.), and then at three follow-ups (six-months [48-mos.], 1-year [54-mos.], and 2-years later [66-mos.]). The results bear implications for the conceptualization and administration of a chronic care model of behavior problems and will provide the first large-scale evaluation of booster treatment in ODD or CD children.